There’s no need to panic, but Chicago is slowly sinking

That sinking sensation in your stomach (the one you thought came from not having your life together) might actually be attributed to the ground beneath your feet ever-so-slowly shifting downward. We're not kidding; according to report from the Chicago Tribunethe land upon which Chicago sits has sunk at least four inches over the past 100 years. The cause? Ancient glaciers.

For those of you who weren't paying attention in high school, here's a quick geology lesson. More than 20,000 years ago, vast regions of the Earth—including present-day Chicago—were buried under huge sheets of glacial ice. When these ice sheets receded roughly 10,000 years ago, the Great Lakes region began to rise as the Earth's crust started to recover after being weighed down by the aforementioned ice. Unfortunately, this great unburdening also caused the Earth's mantle (the liquid magma underneath the crust) to start flowing back into Canada, which in turn has caused the slab of the planet that contains Chicago and the Great Lakes to slowly dip downward.

This geological phenomenon, known as isostatic adjustment, will have the biggest effects on the Great Lakes region. The Tribune spoke to geologists who predict that the Chicago lakefront will rise four inches in the next century—and could rise even higher as result of factors like weather, erosion and global warming. Other cities situated next to the Great Lakes, such as Cleveland and Milwaukee, are also expected to experience similar water level increases.

Enjoy your summer days on the beach, because 100 years from now Chicago may not have much sand left to spread out a towel on.